In 2014, there will be an estimated 1,665,540 new cancer cases diagnosed and 585,720 cancer deaths in the United States. To fight this devastating disease, one of the most important keys is to develop sensitive, accurate, non-invasive, economical, and easily performed assays in the clinic for early cancer detection and diagnosis, monitoring of the disease progression and assessment of treatment response.
Specifically, the top 10 deadliest cancers (lung, colorectal, breast, pancreatic, prostate, leukemia, Non-Hodgkin lymphoma, liver and intrahepatic bile duct, ovarian, and esophageal cancers) are the first leading cause of cancer death in the Western world. In the United States, more than a million new cases of the top 10 cancers are diagnosed and about 420,000 patients die each year. The high mortality partially reflects the lack of universal (pan) tumor specific markers for early tumor detection and diagnosis. In addition, millions of people are at high risk for the top 10 cancers. Those with a high risk for cancer require a reliable and non-invasive test to detect their tumor at early stages. Currently, many tumor markers such as CA19-9, CEA, CA50, CA125, PSA, and CA242 have been investigated for early tumor detection, but none of them are adequate. Furthermore, enzymatic proteins including tumor M2-Pyruvate kinase, elastinase-1 and Galactosyltransferase Isoenzyme II have been explored for cancer diagnosis. The results indicated that those markers seem to have limited value in cancer diagnosis. Non-coding RNAs, macrophage inhibitory cytokine 1 (MIC-1), and CEACAM1 (a member of the CEA antigen family) have also been investigated. Unfortunately, most are still in preclinical evaluation or have limited application in early cancer detection. In summary, no biomarkers or biomarker assays are presently available for cancer early detection and diagnosis. Therefore, tumor specific biological markers and their binding ligands are desperately desired for development of biomarker assays for early cancer detection and diagnosis.
Accordingly, there is a need in the art for a tumor specific, sensitive, non-invasive, economical, and easily performed assay for early cancer detection and diagnosis, monitoring of the disease progression and assessment of treatment response.